Celtic were on Tuesday pursuing a move to bring Newcastle United goalkeeper Fraser Forster back to Parkhead on loan.

And the giant Englishman is poised to rejoin the Scottish Cup holders on a 12-month deal following a lengthy pursuit by manager Neil Lennon.

Celtic are keen to seal the switch before tonight's 11pm European signing deadline for the Europa League play-off round, first leg with Switzerland's FC Sion.

If that proves impossible, however, Forster could return for Sunday's SPL visit from St Johnstone Initially warned by Newcastle manager Alan Pardew that the 23-year-old was going nowhere, Celtic have persevered, despite repeated rebuttals.

On Tuesday night, Celtic insisted no deal is yet in place and other goalkeeping options are still on the table.

But Sportsmail understands the Barclays Premier League club are finally ready to let Forster return to Glasgow.

Croatian international Stipe Pletikosa, Belgian Stijn Stijnen and Polish keeper Grzegorz Sandomierski have all been the subject of interest from Parkhead this summer.

After playing 36 games and winning a Scottish Cup medal last season, however, Forster has always been Lennon's first choice ahead of Pole Lukasz Zaluska.

Meanwhile, Sion are poised to risk expulsion from the Europa League by fielding five of their banned players at Parkhead on Thursday.

They are facing sanction from UEFA and FIFA after signing Jose Goncalves, Mario Mutsch, Gabri, Billy Ketkeophomphone and Pascal Feindouno this summer.

FIFA have warned that the transfer embargo imposed for enticing goalkeeper Essam El-Hadary to break his contract with Al-Ahly does not end until January.

But Sion boss Laurent Roussey said he will field his new signings in Glasgow after the club won a civil-court verdict in Switzerland last week.

'I believe every player is available,' he said. 'They qualify to play in the league, so why not also in Europe?

'If they are to tell us these players can't play, then it will be a huge shock and a huge disappointment.

'A big reason these players came here was to play in the Europa League. They want to face Celtic.'

Sion have taken their fight to the Court of Arbitration for Sport after FIFA and UEFA both warned of trouble if they continue to rebel.

Former Hearts defender Goncalves insists the players are concentrating their efforts on Celtic.

'I will be sad if I can't play, but we are ready and concentrating on the game,' he said.

'All the other stuff needs to be sorted out.

'Since the start of the season it has been like this. It hasn't changed the preparation for any game this season and won't for Thursday.

'I don't know what's really going on - if FIFA can do something or not. The people at the club don't bother us with the information.

'Everyone could play in the league last weekend, so it was not a problem.'